I haven't seen any software available to the public (fire departments)Since all apparatus dealers use computers, I would think they could give you a specification converted to Microsoft word on a CD or disk. This way you could go in and modify it with your department name, legal requirments, etc. I was a member of a new truck committee once and thats how we started. We met with a couple of different manufactures and had them create some general spec's. We then cut and pasted them together into a spec that met our departments needs. There are a couple of good books out through Fire Engineering that are helpful. Goodluck!

I have helped spec out both EMS rigs and Fire Trucks and we always work off specs from a manufacturer. You have to be careful though they try to "slant" them to the way they build. But with a little bit if effort it works well and is the only way to go.

I don't know of any commercially available software either. I do know that Wheeled Coach & Fast Lane both have "In House" spec generating programs and I'm sure other builders do to.

I think it would help you get better information if you could clarify what you're after.

Are you looking for something to generate the "boiler plate" and total written spec or are you looking for tools / utilities to help you with the selection of all your components.

Several apparatus builders have guides & check list available from their web sites.

My suggestion would be to write a performance based spec.
Example:
Must be 4WD
Must have seating for 6 (incl. operator) with at least 3 in air packs
Must have 1000 U.S. Gal water tank capacity
Must have a 1250 U.S. Gal per Minute Pump Capacity
Priority must be given to minimizing wheel base, Overall length, and turning radius.

Then you can submit that spec. to several builders for them to create a design proposal. Then you take the one you like best and start adding & removing things from it as needed.

As was mentioned before - watch out for dealers who will slant things to their benefit.

Ex. Builder X uses 3/16" aluminum tread plate & Builder Y uses 1/8" Tread plate - Make sure you remove the thickness from your final spec. (unless it's a critical area where you want/need a specific material) - this will allow more builders to bid on your vehicle.

Also if you can be more specific on the type of truck you're working on (Engine, Ladder, Rescue, etc.) perhaps I can steer you toward some more specific resources.